Table 2.

OR and 95% CI for gallbladder cancer in relation to gallstone using self-reported and image-verified gallstone.

Self-reported gallstone historyaSelf-reported gallstone using stringent definitionbGallstone history as determined by imaging techniquesc
Gallstone historyN (cases|controls)OR (95% CI)dPdN (cases|controls)OR (95% CI)dPdN (cases|controls)OR (95% CI)ePe
Never693|2,455Reference693|2,455Reference580|787Reference
Ever468|6010.0≤0.001145|544.5≤0.001208|582.0≤0.001
(8.0–12.8)(3.5–5.8)(1.5–2.7)
  • Note: Missing values were excluded from analysis.

  • Abbreviations: CI, confidence interval; OR, odds ratio.

  • aSelf-reported gallstone; as per reported by study participant either present/not present.

  • bSelf-reported gallstone using stringent definition. Gallstone history was ascertained using definition of self-reported gallstone; however, those gallstones diagnosed within a year prior to the date of diagnosis of gallbladder cancer for cases or within a year prior to the date of interview for controls were excluded from the analysis.

  • cGallstone history as determined by imaging techniques (USG, MRI, and CT scans) and using breast cancer cases as a control group.

  • dAdjusted for age (continuous), education (less than 5 years schooling, ≥5 years of education), current residential region (north, northeast, central, west, and south), gender, waist-to-hip ratio (continuous), tobacco chewing and tobacco smoking (yes/no), per capita per month mustard oil consumption (continuous), per capita per week fresh fish consumption (continuous).

  • eSame as d, except not adjusted for gender and additionally adjusted for the number of full-term pregnancies.